Pipetting systems are widely used in the pharmaceutical industries, as well as in industries dealing in cosmetics, food and beverage production. These systems are also used in clinical research applications. These systems are used to aspirate and dispense relatively small and/or preselected volumes of liquids from one receptacle to another. Conventional pipetting systems generally include a housing that comprises a piston and a plunger to enable dispensing and aspiring of liquids. A rigid plastic tip is usually also attached to the pipette, at one end, to enable the transfer and to prevent contamination of liquids by successive samples, often disposable plastic tips are used. Unfortunately, conventional pipetting systems have several shortcomings and problems associated with their use.
One problem associated with the use of these systems deal with the operation of transferring liquids from one receptacle into another. Operations of conventional pipttes need to be manually performed by applying force to the plunger head, usually with a thumb or a finger, in order to actuate the piston. Even if the plunger can be motorized, the user still needs to tightly grip the pipette, especially when mounting and removing the tip from the tip holder. Since repetitive and frequent operation of the pipette is required every day, continued use of these systems contributes to an increased risk of hand and shoulder injuries and may lead to other related ailments often associated with repetitive stress injuries.
A second problem associated with the use of conventional pipettes is the accuracy and range of volume that can be transferred with such devices. Precise measurements of liquids are difficult to achieve and different transfer of volumes in a wide range cannot be accomplished by a single device and therefore different devices and different corresponding tips have to often be utilized. Even then, accuracy is difficult to achieve using current disposable tips as they need to be made from rigid materials in order to allow for proper mounting of the tip to the device. Unfortunately, the mounting of such tips still leaves a large air gap between the piston of the device and the liquid being aspirated and/or dispensed. This gap subsequently affects the accuracy of the actual volume being transferred. The effect of inaccurate dispensation/aspiration is more significant and noticeable when small volumes of liquid are being transferred. As with regards to range of volume supported, the changing of the devices and/or their associated tips affects the overall labor and cost requirements which can burden the overall operation.
A related problem associated with using prior art pipettes that require disposable plastic tips is environmental concerns. As environmental awareness has increased, a great deal of attention is being paid to reducing the environmental impact by minimizing the need to utilize disposable plastic tips.
Consequently, it is desirable to have an improved apparatus and method which can overcome some of the problems associated with the prior art systems as enumerated.